Artificial leather for vehicle interior material and vehicle interior material comprising same

ABSTRACT

An artificial leather for a vehicle interior material includes: a fabric layer comprising a fiber layer; a skin layer disposed on the fabric layer and comprising a thermoplastic polyolefin (TPO); and a surface treatment layer disposed on the skin layer.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0000125, filed on Jan. 4, 2021, the entire contents of which are incorporated herein by reference.

FIELD

The present disclosure relates to an artificial leather for a vehicle interior material and to a vehicle interior material including the same.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Interior materials applied to vehicles are materials that are directly touched and contacted by drivers and passengers. Various materials ranging from plastic resins to natural leather are applied in order to satisfy a variety of desires of consumers as well as the basic decorative function of parts. In particular, with the recent increase in the convenience and comfort of vehicles, the level of aesthetic appearance and sense of luxury desired by consumers is increasing. Accordingly, the application of various soft materials such as fiber, artificial leather, natural leather and the like, rather than conventional plastic materials, to interior materials, is increasing.

In particular, artificial leather for interior materials applied to vehicles is a material that is directly touched and contacted upon driving by a consumer, and is desired to have high fire resistance, light fastness, durability, and slow long-term aging, in addition to decorative functions inside the vehicle. Moreover, various properties that improve the usefulness of parts, such as formability, enabling parts to be sewn, a soft cushion feeling and the like, are desired. Furthermore, in order to satisfy a variety of needs of consumers, various techniques that provide deodorization and other capability are being actively developed.

In general, examples of artificial leather applied to vehicles include PU artificial leather and PVC artificial leather configured such that a polymer resin layer such as PVC, PU, etc., and a fiber layer woven/knitted with polyester, nylon, etc. are laminated. However, artificial leather that is conventionally used contains plasticizers, flame retardants, and organic solvents, and thus may be harmful to the human body and odorous due to the generation of organic compounds. Moreover, when conventional artificial leather is applied to vehicle interior materials, particularly when applied to backboard wrapping, tearing, pressing, and lifting after application may occur, and thus applicability to parts, such as part formability and part performance, may be low.

SUMMARY

The present disclosure provides artificial leather for a vehicle interior material, which is harmless to the human body due to the absence of additives such as flame retardants or plasticizers, and is capable of improving applicability to parts, such as part formability and part performance, and a vehicle interior material including the same.

One form of the present disclosure provides an artificial leather for a vehicle interior material, including: a fabric layer including a fiber layer; a skin layer disposed on the fabric layer and including a thermoplastic polyolefin (TPO); and a surface treatment layer disposed on the skin layer.

The thermoplastic polyolefin (TPO) may include, based on a total of 100 wt % of TPO, 50 to 80 wt % of a thermoplastic vulcanizate (TPV) and 20 to 50 wt % of an olefin resin.

The thickness of the skin layer may be 0.1 to 0.8 mm.

The thermoplastic vulcanizate (TPV) may include, based on a total of 100 wt % of TPV, 30 to 70 wt % of a non-crosslinked TPV resin and 40 to 80 wt % of a partially crosslinked or crosslinked TPV resin.

The olefin resin may include at least one selected from the group consisting of polypropylene (PP) and polyethylene (PE).

The surface treatment layer may be formed through treatment using a mixture of a primer including chlorinated polyolefin and polyurethane and a top-coating agent including polyurethane.

The primer may include, based on a total of 100 wt % of the primer, 1 to 10 wt % of chlorinated polyolefin, 10 to 30 wt of polyurethane, and 60 to 85 wt % of a solvent.

The thickness of the fabric layer may be 0.6 to 1.6 mm.

The artificial leather may have a static load elongation of 30 to 130% and an elongation at break of 120 to 180%.

In addition, the present disclosure provides a vehicle interior material, including: the artificial leather described above; a cushion layer located under the artificial leather and configured to absorb shocks; and a substrate adhered to the cushion layer using an adhesive, in which the adhesive may be a rubber-based adhesive including a crosslinking agent.

The vehicle interior material may include polyethylene (PE) between the cushion layer and the substrate.

The crosslinking agent may include a silane-based crosslinking agent.

The rubber-based adhesive may include at least one selected from the group consisting of a chloroprene-based rubber adhesive and a polyurethane adhesive.

The substrate may include at least one selected from the group consisting of polypropylene (PP) plastics and polycarbonate (PC)/ABS (acrylonitrile butadiene styrene) plastics.

The artificial leather for a vehicle interior material according to the present disclosure is harmless to the human body due to the absence of additives such as flame retardants or plasticizers, does not generate harmful substances during incineration, and is environmentally friendly due to the use of a recyclable resin.

In addition, the artificial leather for a vehicle interior material according to the present disclosure is not likely to cause undesired quality such as stickiness, glossiness, cracking, etc. due to plasticizer migration. Even when it is applied to vehicle interior materials, tearing, pressing, and lifting after application do not occur, thus exhibiting superior applicability to parts, such as part formability and part performance.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

FIG. 1 is a cross-sectional view schematically showing an artificial leather 10 for a vehicle interior material according to one form of the present disclosure; and

FIG. 2 is a cross-sectional view schematically showing a vehicle interior material 1 according to another form of the present disclosure.

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

Throughout the drawings, the same reference numerals will refer to the same or like elements. For the sake of clarity of the present disclosure, the dimensions of structures are depicted as being larger than the actual sizes thereof.

It will be further understood that the terms “comprise”, “include”, “have”, etc., when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. Also, it will be understood that when an element such as a layer, film, area, or sheet is referred to as being “on” another element, it can be directly on the other element, or intervening elements may be present therebetween. Similarly, when an element such as a layer, film, area, or sheet is referred to as being “under” another element, it can be directly under the other element, or intervening elements may be present therebetween.

Unless otherwise specified, all numbers, values, and/or representations that express the amounts of components, reaction conditions, polymer compositions, and mixtures used herein are to be taken as approximations including various uncertainties affecting measurement that inherently occur in obtaining these values, among others, and thus should be understood to be modified by the term “about” in all cases. Furthermore, when a numerical range is disclosed in this specification, the range is continuous, and includes all values from the minimum value of said range to the maximum value thereof, unless otherwise indicated. Moreover, when such a range pertains to integer values, all integers including the minimum value to the maximum value are included, unless otherwise indicated.

When conventional artificial leather is applied to vehicle interior materials, particularly when applied to backboard wrapping, tearing, pressing, and lifting after application may occur, and applicability to parts, such as part formability and part performance, is low, which is undesirable.

Therefore, the inventors of the present disclosure have developed artificial leather for vehicle interior materials, which is harmless to the human body due to the absence of additives such as flame retardants or plasticizers included in artificial leather, avoids undesired quality such as glossiness, cracking and the like by improving the components and amounts of the skin layer included therein, and does not cause tearing, pressing, and lifting after application even when applied to vehicle interior materials, thereby exhibiting superior applicability to parts, such as part formability and part performance, thus culminating in the present disclosure.

FIG. 1 is a cross-sectional view schematically showing an artificial leather 10 for a vehicle interior material according to one form of the present disclosure. With reference thereto, the artificial leather 10 for a vehicle interior material includes a fabric layer 100, a skin layer 200, and a surface treatment layer 300.

The fabric layer 100 is a base substrate of the artificial leather for a vehicle interior material, and the fabric layer may include a fiber layer. Here, the number of fiber layers is not limited, but preferably, a single fiber layer is provided. The artificial leather including the same is not particularly limited, so long as it is able to perform functions such as supporting the skin layer, reinforcing strength, maintaining an elongation, and the like.

The fiber layer may include at least one selected from the group consisting of polyester, nylon, cotton, and polypropylene, but is not limited to including a specific component. Also, the fiber layer is in the form of a nonwoven fabric, preferably a circular knit or a warp knit, and is not limited to a specific form.

Also, the fiber layer may be made into artificial leather through post-treatment with polyurethane, PVA, or a water repellent in order to attain workability and desired properties in the process of manufacturing artificial leather for vehicle interior materials.

The thickness of the fabric layer including the fiber layer may be 0.6 to 1.6 mm, and preferably 0.8 to 1.4 mm. Outside the above range, if the thickness of the fabric layer is too high, the appearance may deteriorate due to excessive wrinkling when wrapping the interior material, whereas if the thickness of the fabric layer is too low, tearing or bursting may occur during wrapping due to the insufficient strength thereof.

The skin layer 200 is disposed on the fabric layer, and is not particularly limited, so long as it is able to maintain the appearance of the artificial leather including the same and perform a function of realizing appropriate durability.

The skin layer may include a thermoplastic polyolefin (TPO), and may not include a plasticizer.

Specifically, the thermoplastic polyolefin (TPO) is not particularly limited, so long as it is one crosslinked from an olefin-based resin or an olefin-based rubber as a main component, and the thermoplastic polyolefin (TPO) preferably includes a thermoplastic vulcanizate (TPV) and an olefin resin, and more preferably includes a partially crosslinked thermoplastic vulcanizate (TPV) and an olefin resin.

The thermoplastic vulcanizate (TPV) is a binary polymer material characterized by a structure in which crosslinked rubber particles, which are soft segments, are finely dispersed in a thermoplastic resin, which is a hard segment. The TPV may be an olefin-based TPV, and may be prepared by melt-blending polypropylene as a base polymer and EPDM, oil, filler, etc. using a twin-screw extruder. TPV has the properties of vulcanized rubber at room temperature and has excellent plastic deformation at high temperatures, which allows the matrix to flow, so it has excellent forming processability, mechanical strength, weather resistance, and heat resistance. Moreover, TPV is lightweight due to the low specific gravity thereof, and may be colored, and is also advantageous because the compression set, heat resistance, tensile strength, and oil resistance are superior compared to TPO.

Preferably, the thermoplastic vulcanizate (TPV) includes a non-crosslinked TPV, a partially crosslinked TPV, and a crosslinked TPV. The non-crosslinked TPV has higher heat resistance than a general olefin resin, and does not use a crosslinking agent, so there is little change in odor and properties, and superior light resistance and heat resistance are exhibited. Meanwhile, the partially crosslinked TPV and the crosslinked TPV are capable of inhibiting damage by pressing due to other causes at high temperatures, and thus have an advantage of inhibiting surface damage due to external force at high temperatures.

Accordingly, the thermoplastic vulcanizate (TPV) may include, based on a total of 100 wt % of TPV, 30 to 70 wt %, of a non-crosslinked TPV, and 40 to 80 wt % of a partially crosslinked or crosslinked TPV. Outside the above range, if the amount of the non-crosslinked TPV is too small, calendering processability may deteriorate, whereas if the amount of the non-crosslinked TPV is too large, the appearance may deteriorate during the forming process due to the decreased melt strength thereof. In addition, if the amount of the partially crosslinked or crosslinked TPV is too small, poor formability, such as insufficient elongation, may occur. On the other hand, if the amount of the partially crosslinked or crosslinked TPV is too large, it is difficult to perform calendering, and surface defects may occur due to non-melted materials.

The olefin resin, which is an aliphatic unsaturated hydrocarbon, may be an olefin resin in which a monomer having a carbon double bond in a molecular structure is polymerized, and is not limited to including a specific component, but preferably includes polypropylene (PP) and polyethylene (PE).

The thermoplastic polyolefin (TPO) may include 50 to 80 wt % of the thermoplastic vulcanizate (TPV) and 20 to 50 wt % of the olefin resin. Outside the above range, if the amount of the TPV is too small or the amount of the olefin resin is too large, mechanical properties may be weakened and softening may occur, and thus the surface may be deteriorated due to the formation of pressing marks upon lamination to artificial leather for a vehicle interior material. On the other hand, if the amount of the TPV is too large or the amount of the olefin resin is too small, economic efficiency is low due to the high manufacturing cost thereof, and moreover, the viscosity is excessively high, undesirably leading to low productivity.

The thickness of the skin layer may be 0.1 to 0.8 mm, and preferably 0.2 to 0.7 mm. Outside the above range, if the thickness of the skin layer is too low, the skin layer may be exposed or torn after forming, whereas if the thickness thereof is too high, the product may become hard and formability may decrease.

Specifically, the artificial leather for a vehicle interior material according to the present disclosure includes the skin layer in which the thermoplastic polyolefin (TPO) includes the thermoplastic vulcanizate (TPV) and the olefin resin in specific amounts. Therefore, it is harmless to the human body, does not generate harmful substances during incineration, and is environmentally friendly due to the use of a recyclable resin, and moreover, quality problems such as stickiness, glossiness, cracking, etc. due to plasticizer migration do not occur.

The surface treatment layer 300 is located on the skin layer, and is not particularly limited, so long as it is able to improve scratch resistance, fouling resistance, surface properties, and a tactile sensation.

The surface treatment layer may be formed through treatment using a mixture of a primer and a top-coating agent. Specifically, the primer may include chlorinated polyolefin and polyurethane, and the top-coating agent may include polyurethane.

The primer functions to increase the adhesion of the aqueous surface treatment agent, and preferably includes 1 to 10 wt % of chlorinated polyolefin, 10 to 30 wt % of polyurethane, and 60 to 85 wt % of distilled water as a solvent.

Outside the above range, if the amount of chlorinated polyolefin is too small, properties may be deteriorated due to poor adhesion of the surface treatment layer, or the appearance after forming may become poor, whereas if the amount of chlorinated polyolefin is too large, it is difficult to realize surface properties suitable for application to vehicles. Also, if the amount of polyurethane is too small, the surface properties may be deteriorated, whereas if the amount of polyurethane is too large, the properties may be deteriorated due to poor adhesion of the surface treatment layer.

The top-coating agent functions to impart a desired tactile sensation and surface durability, and preferably includes polyurethane using distilled water as a solvent. Moreover, a silicone- or fluorine-based antifouling coating agent may be further included in order to add an antifouling coating.

Specifically, the artificial leather for a vehicle interior material according to the present disclosure includes the fabric layer, the skin layer, and the surface treatment layer, having the above characteristics, which are sequentially laminated, and has a static load elongation of 30 to 130% and an elongation at break of 120 to 180%. Outside the above range, if the static load elongation is too low or the elongation at break is too low, the artificial leather may not be stretched but may be torn or wrinkled when the wrapping process is performed using a thermoforming process in order to manufacture a vehicle interior material. On the other hand, if the static load elongation is too high or the elongation at break is too high, lifting may occur due to shrinkage when manufacturing a vehicle interior material. In summary, the artificial leather for a vehicle interior material according to the present disclosure does not cause tearing, pressing, and lifting after application when applied to a vehicle interior material, and thus is advantageous because of superior applicability to parts, such as part formability and part performance.

In particular, since the skin layer in the artificial leather for a vehicle interior material according to the present disclosure includes the thermoplastic polyolefin (TPO) and the olefin resin at an optimal ratio, the skin layer may be attached to the fabric layer and then the surface treatment layer may be formed on the surface of the skin layer opposite the surface attached to the fabric layer, using a calendaring process having high cost competitiveness, and moreover, an embossed pattern may be formed on the surface of the surface treatment layer using embossing rolls or release paper.

FIG. 2 is a cross-sectional view schematically showing a vehicle interior material 1 according to another form of the present disclosure. With reference thereto, the vehicle interior material 1 includes an artificial leather 10 for a vehicle interior material, a cushion layer 20, and a substrate 30.

Here, the artificial leather 10 for a vehicle interior material may be the same as the artificial leather 10 according to one form of the present disclosure as described above.

The cushion layer 20 may be located under the artificial leather for a vehicle interior material, and may function to impart a cushion feeling to the vehicle interior material including the same so as to absorb shocks, and may include, for example, at least one selected from the group consisting of polypropylene (PP), polyurethane (PU), and polyethylene terephthalate (PET), but is not limited to including a specific component.

The substrate 30 is a basic part of the vehicle interior material, and may be attached to the cushion layer using an adhesive. The substrate may be a typical plastic part for an interior material capable of being used in the present disclosure, for example, a part including at least one selected from the group consisting of polypropylene (PP) plastics and polycarbonate (PC)/ABS (acrylonitrile butadiene styrene) plastics, but is not limited to including a specific plastic. The substrate uses a coating layer and an adhesive, which will be described later, and thus pretreatment for enhancing adhesion, such as etching or primer treatment, is not desired.

The vehicle interior material of the present disclosure may include a coating layer (not shown) between the cushion layer and the substrate, rather than pre-treating the substrate, thereby improving adhesion between the cushion layer and the substrate. Specifically, the coating layer may include at least one selected from the group consisting of polyethylene (PE) and polypropylene (PP), capable of contributing to increasing adhesion by improving adhesive wettability after heating, and is not limited to including a specific component, but preferably includes polyethylene.

Moreover, in the present disclosure, an adhesive may be used to enhance adhesion between the cushion layer located under the artificial leather and the substrate. Here, it is preferable to use a rubber-based adhesive added with a crosslinking agent in order to inhibit a lifting phenomenon from the substrate even under harsh environmental conditions such as heat, moisture, and cold.

The rubber-based adhesive may be a typical rubber-based adhesive capable of being used in the present disclosure, for example, a chloroprene-based rubber adhesive or a polyurethane adhesive, and is not limited to including an adhesive of a specific component.

The crosslinking agent may be, for example, a silane-based crosslinking agent capable of reacting with a rubber-based adhesive to thus inhibit lifting of the cushion layer and the substrate, and may include at least one selected from the group consisting of alkoxysilanes, such as vinylethoxysilane, vinyl-tris-(β-methoxyethoxy)silane, methacryloylpropyltrimethoxysilane, γ-amino-propyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane and trimethoxysilane, epoxy silanes, such as triepoxy silane, aminosilanes, such as butylaminosilane and epoxy-aminosilane, alkylsilanes, such as methylsilane, dimethylsilane, vinylmethyldimethylcyclotrisiloxane, dimethylsilane-oxocyclopentane, cyclohexylsilane and cyclohexyldisilane, silane, and disilane, and is not limited to including a specific component.

Specifically, the vehicle interior material, including the artificial leather for a vehicle interior material according to the present disclosure and manufactured using the cushion layer, the substrate, the coating layer and the adhesive satisfying the above characteristics, is advantageous because tearing, pressing, and lifting after application do not occur.

A better understanding of the present disclosure may be obtained through the following examples. However, these examples are merely set forth to illustrate the present disclosure, and are not to be construed as limiting the scope of the present disclosure.

Example 1 and Comparative Examples 1 to 5: Manufacture of Artificial Leather for Vehicle Interior Material

The components in the amounts shown in Table 1 below were mixed and kneaded using a Super mixer to form a skin layer, which was then laminated with a fabric layer using calendering process, followed by thermal compression. Thereafter, a surface treatment layer was formed on the skin layer through treatment with a mixture of a primer including the components in the amounts shown in Table 1 below and a top-coating agent, thereby manufacturing artificial leather for a vehicle interior material.

TABLE 1 Surface treatment layer Classification (primer) Skin layer Fabric layer Example 1 CPP 5-20%, TPV 50-80% Brushed terry PU 5-20% Olefin resin 20-50% Comparative CPP 1-3%, TPV 40% Lining terry Example 1 PU 20-25% Olefin resin 60% Comparative CPP 3-5%, TPV 40% Lining terry Example 2 PU 20-25% Olefin resin 60% Comparative CPP 3-5%, TPV 40% Brushed terry Example 3 PU 20-25% Olefin resin 60% Comparative CPP 1-3%, TPV 40% H/KNIT Example 4 PU 20-25% Olefin resin 60% Comparative CPP 3-5%, TPV 40% Lining terry Example 5 PU 20-25% Olefin resin 60% * Surface treatment layer = surface treatment layer including PU containing less than 2% silicone as top-coating agent. * Skin layer thickness = 0.40-0.60 * Fabric layer thickness = 0.5-0.7 * Fabric layer composition = Brushed terry (polyester 100%), Lining terry (polyester 100%), H/KNIT (polyester 100%), S/KNIT (polyester 100%)

Examples 2 to 4 and Comparative Examples 6 to 9: Manufacture of Vehicle Interior Material Including Artificial Leather for Vehicle Interior Material

The artificial leather for a vehicle interior material manufactured in Example 1 was disposed as the uppermost layer, and a cushion layer and a coating layer (Comparative Examples not including a coating layer are represented as “-” in the following table) were adhered thereunder as shown in Table 2 below, after which an adhesive was applied on the attachment surface on the substrate and the coating layer, followed by thermoforming, thereby manufacturing vehicle interior materials.

TABLE 2 Cushion Coating Classification layer layer Adhesive Substrate Example 2 PU foam Presence CR changed PP (PE) (crosslinking ↑) Example 3 PU foam Presence CR changed PC-ABS (PE) (crosslinking ↑) Example 4 PU foam — CR changed PP (crosslinking ↑) Comparative Absence — General CR PP Example 6 Comparative PP foam — CR changed PP Example 7 (crosslinking ↑) Comparative PU foam — General CR PP Example 8 Comparative PU foam Presence General CR PP Example 9 (PE) * Crosslinking agent of adhesive (silane crosslinking agent) = Use of alkoxysilane including methyltriethoxysilane and trimethoxysilane

Evaluation of Properties

-   -   Surface treatment adhesion: When applying the surface treatment         agent after attachment of TPO and a fiber layer through         calendering, whether the upper surface of TPO was stably treated         without coating marks was determined     -   Elongation at break: According to MS300-31:2020, pertaining to         standard test method specifications for leather, artificial         leather and sheets, measurement was performed at a tensile speed         of 200 mm/min and a gauge length of 100 mm     -   Static load elongation: According to MS300-31:2020, pertaining         to standard test method specifications for leather, artificial         leather and sheets, elongation was measured after 10 minutes         under a load of 8 kg at a gauge length of 100 mm     -   Light resistance: According to MS300-31:2020, pertaining to         standard test method specifications for leather, artificial         leather and sheets, whether a test sample became         discolored/faded based on a grayscale color change at a total         dose of 84 MJ/m² of a Xenon lamp light source using a test         device of ISO 105 was determined     -   Formability: Using a thermoforming process, the artificial         leather was located at the uppermost position and a plastic part         to be wrapped was disposed thereunder, after which air was         sucked from the region beneath the plastic part and vacuum         attachment was thus performed, and then the appearance was         determined depending on whether the artificial leather was         normally formed/attached to the plastic (problem phenomena:         wrinkling, tearing, etc.).     -   Pressability after heating: The artificial leather was placed in         a chamber at 90° C., a 1 kg weight was placed thereon, and the         extent of pressing of the artificial leather due to the load of         the weight after 1 hour was determined.     -   Lifting after exposure to complex environment: The part was         allowed to stand for a total of 3 cycles under changing         environmental conditions (90° C.×4 hours→−40° C.×3 hours→50° C.,         95% RH×7 hours), after which whether the plastic part and the         artificial leather were separated and whether lifting occurred         were determined.     -   Creep durability: According to MS715-73:2020, pertaining to         adhesive standards, the substrate and the skin material were         attached using an adhesive, after which a 100 g weight was hung         from a portion of the skin material and left at 80° C. for 1         hour, and the peeled length between the substrate and the skin         material due to heat and the load of the weight was then         measured.

Test Example 1: Evaluation of Properties Depending on Composition of Artificial Leather for Vehicle Interior Material

The artificial leather for a vehicle interior material was manufactured according to Example 1 and Comparative Examples 1 to 5, and the properties thereof, such as surface treatment adhesion and the like, were evaluated depending on the composition thereof. The results thereof are shown in Table 3 below.

TABLE 3 Properties Static load Surface elongation Pressability treatment Elongation (width Light after Classification adhesion at break direction) resistance Formability heating Example 1 Good 80/170 105 Grade 4 OK Good Comparative Poor 87/122 44 Grade 4 NG (torn) Pressed Example 1 Comparative Good 87/122 44 Grade 4 NG (torn) Pressed Example 2 Comparative Good 80/170 105 Grade 4 OK Pressed Example 3 Comparative Poor 81/150 57 Grade 4 OK Pressed Example 4 Comparative Good 87/122 44 Grade 4 NG (torn) Pressed Example 5 Target Good 150-200 55-130 Grade 3-5 Pass Pass properties

As is apparent from Table 3, Comparative Examples 1 and 4, in which the amount of chlorinated polyolefin in the primer used to manufacture the surface treatment layer did not satisfy the numerical range of the present disclosure, exhibited insufficient surface treatment adhesion. Also, in Comparative Examples 1 to 5, in which the amount of the thermoplastic vulcanizate (TPV) used as the thermoplastic polyolefin (TPO) in the skin layer did not satisfy the numerical range of the present disclosure (below the lower limit), the shape thereof was changed upon heating due to thermoplastic properties and thus a pressing phenomenon occurred, indicating that pressability after heating was deteriorated.

Also, in Comparative Examples 1, 2, and 5 using lining terry as the fabric layer, tearing occurred due to variation in formability, indicating that the fabric layer influenced elongation to some extent and thus affected formability.

Specifically, since the skin layer in the artificial leather for a vehicle interior material according to the present disclosure includes the thermoplastic polyolefin (TPO) and the olefin resin at an optimal ratio, the artificial leather for a vehicle interior material according to the present disclosure is harmless to the human body due to the absence of additives such as flame retardants or plasticizers, does not generate harmful substances during incineration, is environmentally friendly due to the use of a recyclable resin, and does not cause undesired quality such as stickiness, glossiness, and cracking due to plasticizer migration. Moreover, the artificial leather for a vehicle interior material according to the present disclosure may exhibit static load elongation of 30-130% and elongation at break of 120-180%, and even when applied to vehicle interior materials, tearing, pressing, and lifting after application do not occur, ultimately manifesting superior applicability to parts, such as part formability and part performance.

Test Example 2: Evaluation of Properties of Vehicle Interior Material

According to Examples 2 to 4 and Comparative Examples 6 to 9, vehicle interior materials were manufactured, and the properties thereof, such as creep durability and the like, were evaluated. The results thereof are shown in Table 4 below.

TABLE 4 Properties Lifting after exposure to Creep Classification complex environment durability Example 2 No lifting 5 Example 3 No lifting 2 Example 4 No lifting 9 Comparative Example 6 Lifting 60 Comparative Example 7 Lifting 45 Comparative Example 8 Lifting 41 Comparative Example 9 Lifting 20 Target performance No lifting 20 mm or less

As is apparent from Table 4, in Comparative Example 6 not including the cushion layer, it was confirmed that adhesive wettability was deteriorated and thus lifting after exposure to the complex environment occurred. Also, in Comparative Example 7, including the cushion layer made of PP foam, rather than PU foam, a high creep durability value resulted, and thus adhesion was poor, indicating that lifting occurred after exposure to the complex environment.

Also, in Comparative Examples 8 and 9, using a general adhesive not added with the crosslinking agent, creep durability was high and thus adhesion became weak and lifting occurred after exposure to the complex environment, compared to Examples 3 and 4 using an adhesive added with the crosslinking agent.

Moreover, Example 2 and Example 3 including the coating layer had low creep durability values compared to the vehicle interior material not including the coating layer, so adhesion was strengthened, indicating that lifting did not occur after exposure to the complex environment.

Also, in Examples 2 and 3, using different types of substrates, there were differences in the creep durability value, but lifting did not occur after exposure to the complex environment.

Specifically, the vehicle interior material including the artificial leather for a vehicle interior material according to the present disclosure and manufactured using the cushion layer, the substrate, the coating layer and the adhesive satisfying the above characteristics is advantageous because tearing, pressing, and lifting after application do not occur. 

What is claimed is:
 1. An artificial leather for a vehicle interior material, the artificial leather comprising: a fabric layer comprising a fiber layer; a skin layer disposed on the fabric layer and comprising a thermoplastic polyolefin (TPO); and a surface treatment layer disposed on the skin layer.
 2. The artificial leather of claim 1, wherein the thermoplastic polyolefin (TPO) comprises, based on a total of 100 wt % of TPO, 50 to 80 wt % of a thermoplastic vulcanizate (TPV) and 20 to 50 wt % of an olefin resin.
 3. The artificial leather of claim 2, wherein the thermoplastic vulcanizate (TPV) comprises, based on a total of 100 wt % of TPV, 30 to 70 wt % of a non-crosslinked TPV resin and 40 to 80 wt % of a partially crosslinked or crosslinked TPV resin.
 4. The artificial leather of claim 2, wherein the olefin resin comprises at least one selected from the group consisting of polypropylene (PP), polyethylene (PE), and mixtures thereof.
 5. The artificial leather of claim 1, wherein a thickness of the skin layer is 0.1 to 0.8 mm.
 6. The artificial leather of claim 1, wherein the surface treatment layer is formed through a treatment using: a mixture of a primer comprising chlorinated polyolefin and polyurethane; and a top-coating agent comprising polyurethane.
 7. The artificial leather of claim 6, wherein the primer comprises, based on a total of 100 wt %, of the primer, 1 to 10 wt % of chlorinated polyolefin, 10 to 30 wt, of polyurethane, and 60 to 85 wt. % of a solvent.
 8. The artificial leather of claim 1, wherein a thickness of the fabric layer is 0.6 to 1.6 mm.
 9. The artificial leather of claim 1, wherein the artificial leather has a static load elongation of 30 to 130% and an elongation at break of 120 to 180%.
 10. A vehicle interior material, comprising: an artificial leather comprising: a fabric layer comprising a fiber layer, a skin layer disposed on the fabric layer and comprising a thermoplastic polyolefin (TPO), and a surface treatment layer disposed on the skin layer; a cushion layer located under the artificial leather and configured to absorb shocks; and a substrate adhered to the cushion layer using an adhesive, wherein the adhesive is a rubber-based adhesive including a crosslinking agent.
 11. The vehicle interior material of claim 10, further comprising a coating layer comprising polyethylene (PE) between the cushion layer and the substrate.
 12. The vehicle interior material of claim 10, wherein the crosslinking agent comprises a silane-based crosslinking agent.
 13. The vehicle interior material of claim 10, wherein the rubber-based adhesive comprises at least one selected from a group consisting of a chloroprene-based rubber adhesive, a polyurethane adhesive, and mixtures thereof.
 14. The vehicle interior material of claim 10, wherein the substrate comprises at least one selected from a group consisting of polypropylene (PP) plastics, polycarbonate (PC)/ABS (acrylonitrile butadiene styrene) plastics, and mixtures thereof. 